Reference voltages are used in many applications ranging from memory, analog, and mixed-mode to digital circuits. Bandgap reference (BGR) circuits are used for generating such reference voltages. Demand for low-power and low-voltage operation is increasing with the spread of battery-operated portable applications. The reference voltage of conventional BGR is 1.25 V, which is nearly the same voltage as the bandgap of silicon. This fixed output voltage of 1.25 V limits low voltage operation of BGR circuits.